Oil change with vacuum

[KandJ72]

I know I’m kinda the odd-man out here at times due to the boats age and the fact we have Ford based PCM engines. So here’s my head scratcher. I picked up a decent manual vacuum pump to draw through the dipstick, when I used it I only pulled about 1.5-2 quarts out. Now the ‘76 PCM 351W has what pretty much seems to be a center sump, I read something about it that they did that so no matter what pitch/roll or plane you were on the pickup would always have oil. The tube is actually not in line with the sump though it’s closer to the front of the engine on the right side. So I’m thinking when that hose is bottoming out it’s just hitting high up in the pan and I’m really not getting it out. There’s 2 cut marks on the stick that pretty much correspond when I added back in 2 quarts 1 by 1, bottom line showed 1st quart then top line for the 2nd. HOWEVER there is another line a good inch or more higher up. Not knowing what’s actually in there I don’t want to go for broke and just overfill it to that higher line “assuming” that’s the fill line. They obviously didn’t come with the fancy drain tubes everybody has now, NOR did they come with any room to place a pan under the engine let alone get down to it…. Just wondering if anyone else has had success getting these engines fully drained with a vacuum system. My thought was to just sacrifice the 2 quarts I added, suck them out, squeeze my way down there with a shallow disposable pan, try to pull the plug and then suck out whatever ends up in the pan before trying to get it out. Then add a drain kit and not change it again until she’s hauled out for the winter!!!!
Yes I do know it works, we tried it on the neighbors 5.7 and it pulled well over 4 quarts out so I know it’s not the pump.

[390Express]

Source of the post I know I’m kinda the odd-man out here at times due to the boats age and the fact we have Ford based PCM engines. So here’s my head scratcher. I picked up a decent manual vacuum pump to draw through the dipstick, when I used it I only pulled about 1.5-2 quarts out. Now the ‘76 PCM 351W has what pretty much seems to be a center sump, I read something about it that they did that so no matter what pitch/roll or plane you were on the pickup would always have oil. The tube is actually not in line with the sump though it’s closer to the front of the engine on the right side. So I’m thinking when that hose is bottoming out it’s just hitting high up in the pan and I’m really not getting it out. There’s 2 cut marks on the stick that pretty much correspond when I added back in 2 quarts 1 by 1, bottom line showed 1st quart then top line for the 2nd. HOWEVER there is another line a good inch or more higher up. Not knowing what’s actually in there I don’t want to go for broke and just overfill it to that higher line “assuming” that’s the fill line. They obviously didn’t come with the fancy drain tubes everybody has now, NOR did they come with any room to place a pan under the engine let alone get down to it…. Just wondering if anyone else has had success getting these engines fully drained with a vacuum system. My thought was to just sacrifice the 2 quarts I added, suck them out, squeeze my way down there with a shallow disposable pan, try to pull the plug and then suck out whatever ends up in the pan before trying to get it out. Then add a drain kit and not change it again until she’s hauled out for the winter!!!!
Yes I do know it works, we tried it on the neighbors 5.7 and it pulled well over 4 quarts out so I know it’s not the pump.

The best "oil catch can" for tight spaces that I have found, is a 2 liter bottle, with about a tennis bowl sized hole cut out by the cap. It fits damn near anywhere, and it's collapsable (even if it doesn't fit, you can crunch it in)... the biggest issue, is lack of capacity. If you really wanted to bootleg it, you could "cowboy" (tape in succession) more two liter bottles, or make something long with a catch basin out of PVC.

Be careful, 2 liters is very limited capacity. you'll likely have to put the plug back in, dump it out, and go back at at it at least twice.

[bud37]

....I have a suggestion to try, measure the distance from the top of the dipstick tube to the bottom of the oil pan.......then put some tape around ( mark) the extraction tube at that distance, then stick it in only that far and see what you get out. Sometimes it can hit the bottom and curl back up.

[KandJ72]

Thank you both for the suggestions, I may have to put my Redneck ( I mean Privateer) skills to work on this one. The curve ball is that oil pan sump doesn't really line up with the dipstick tube, must of been during the Iacocca era ....
The 2 liter bottle might do the trick especially if I'm getting the first 2 quarts out with the vacuum. I'll take pics and keep you guys posted on this one.
390Express where can I get a plastic 2 liter of ice cold beer?!?! I don't drink soda

[390Express]

Source of the post Thank you both for the suggestions, I may have to put my Redneck ( I mean Privateer) skills to work on this one. The curve ball is that oil pan sump doesn't really line up with the dipstick tube, must of been during the Iacocca era ....
The 2 liter bottle might do the trick especially if I'm getting the first 2 quarts out with the vacuum. I'll take pics and keep you guys posted on this one.
390Express where can I get a plastic 2 liter of ice cold beer?!?! I don't drink soda

I'd be willing to bet wallmart has you covered!

I stole mine from the marina garbage can. I don't drink that crap (soda) either, unless someone happens to put it in my whiskey.

[KandJ72]

I try my best to avoid that place, they don't sell Rum
How Dare they dilute good whiskey like that!

[Phrancus]

fix attach the suction line of your pump to the bottom of the creatively formed catch pan and there you go.